A certain culture of yeast increases by 50% every three hours. A scientist places 9 grams of the yeast in a culture dish. Is this geometric or arithmetic? Write an explicit formula for this situation. How much yeast will there be after 9 hours?
It is geometric.
The rule is aₙ=9(1.5)ⁿ⁻¹
After 9 hours, there will be 30.375 grams of yeast.
500
Factor x⁴+2x³-9x²-18x completely
x(x+3)(x-3)(x+2)
500
Use the quadratic formula to solve 3x²+10x-7=0.
[-5±√(46)]/3
500
The population of a town is modeled by the function p=25√(3t)+2000, where p is the population and t is the time since 2000. What is the population in 2007?
The population is about 2115 people.
500
Mike can bake a batch of cookies in 40 minutes. Sarah can do the same in one hour. If they work together, how long will it take them to bake one batch of cookies?